THE "SUMMA THEOLOGICA"

Q. 2. ART. _ THE "SUMMA THEOLOGICA" 22
the word signifies exists actually, but only that it exists
mentally. Nor can it be argued that it actually exists,
unless it be admitted that there actually exists something
than which nothing greater can be thought; and this precisely
is not admitted by those who bold that God does not exist.
Reply Obj. 3. The existence of truth in general is selfevident
but the existence of a Primal Truth is not selfevident
to us.
_ECOND ARTICLE.
WHETHER IT CAN BE DEMONSTRATED THAT GOD EXISTS ?
We proceed thus to the Second Article :_
Objection I. It seems that the existence of God cannot
be demonstrated. For it is an article of faith that God
exists. But what is of faith cannot be demonstrated,
because a demonstration produces scientific knowledge;
whereas faith is of the unseen (Heb. xi. i). Therefore it
cannot be demonstrated that God exists.
Obj. 2. Further, the essence is the middle term of demonstration.
But we cannot know in what God's essence
consists, but solely in what it does not consist; as Damascene
says (De Fid. Orth. i. 4-). Therefore we cannot demonstrate
that God exists.
Obi. 3. Further, if the existence of God were demonstrated,
this could only be from His effects. But His
effects are not proportionate to Him, since He is infinite
and His effects are finite; and between the finite and infinite
there is no proportion. Therefore, since a cause cannot be
demonstrated by an effect not proportionate to it, it seems
that the existence of God cannot be demonstrated.
On the contrary, The Apostle says: The invisible things
o] Him are clearly seen, being understood by the things that
are made (Rom. i. 20). But this would not be unless the
existence of God could be demonstrated through the things
that are made; for the first thing we must know of anything
is, whether it exists.
I answer that, Demonstration can be made in two ways:
One is through the cause, and is called a priori, and this